package top.igotcha.mapreduce.join.reducer;

import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Reducer;

import java.io.IOException;

/**
 * @author Gotcha
 * @date 2021/1/12
 * @describe
 */
public class JoinReducer extends Reducer<Text,Text,Text,Text> {
    @Override
    protected void reduce(Text key, Iterable<Text> values, Context context) throws IOException, InterruptedException {
        String first = "";
        String second = "";
        for (Text value : values) {
            if (value.toString().startsWith("p")){
                first = value.toString();
            } else {
                second = value.toString();
            }
        }
        if (first.equals("")){
            context.write(key,new Text("NULL"+"\t"+second));
        } else {
            context.write(key,new Text(first+"\t"+second));
        }
    }
}
